`git stack amend` breaks signatures of child commits

[aohoyd]

Please complete the following tasks

• [X] I have searched the discussions
• [X] I have searched the existing issues

Description

Hi! It looks like git stack amend breaks signature of child commits

Version

git-stack 0.10.6

Steps to reproduce

git checkout -b feature1
echo 1 > 1.txt
git add .
git commit -m "#1"
echo 2 > 2.txt
git add .
git commit -m "#2"
echo 3 > 3.txt
git add .
git commit -m "#3"
git stack

git log --graph --all --pretty="format:%C(auto)%h %C(auto)(%G?) %C(auto)%d %C(auto)%s" -3
# Output:
# * dadd798 (G)  (HEAD -> feature1) #3
# * 333f017 (G)  #2
# * d34c712 (G)  #1
# Note: (G) means that the commit is GPG signed. All commits are ok.

# Switch two commits up
git prev
git prev

# Make a change to #1 commit
echo 1 >> 1.txt
git add .
git amend

git log --graph --all --pretty="format:%C(auto)%h %C(auto)(%G?) %C(auto)%d %C(auto)%s" -3
# Output:
# * d97fde4 (N)  (feature1) #3
# * 251d64a (N)  #2
# * 4604f95 (G)  (HEAD) #1
# Note: (N) means that the commit is not GPG signed. Last two commits are not ok.

Actual Behaviour

In the last git log command you can see that commits #2 and #3 are not GPG signed

Expected Behaviour

All commits should stay signed

Debug Output

No response

[epage]

Wait, so the amended commit was signed? #260 worked? That was all untested code as I don't do signing.

So the problem is with the implementation. We are building on top of git2.

• The amend is performed by creating a fixup commit and then squashing it (which is a commit operation). The API allows us to sign these. git2 allows us to sign these.
• When we cherry-pick the other commits on top, we've implemented this as a rebase operation within git2 so it will detect commits we can drop. The commit provided by this does not support us explicitly signing the commit.

The rebase operation allows us to access the index of each step. We could possibly manually create a commit around that so it could be signed.

[aohoyd]

Wow, that was fast:) thank you!